On July 29, 1958, Congress passed legislation and President Dwight D. Eisenhower signed into law the National Aeronautics and Space Act, establishing NASA.
In the 55 years since, “NASA has become the world’s premier agent for exploration, carrying on in ‘the new ocean’ of outer space a long tradition of expanding the physical and mental boundaries of humanity,” wrote NASA historian Steven J. Dick.
On the space administration’s anniversary, take a look back on five big milestones NASA has achieved so far—and five more to look forward to in the next few decades.1958: Explorer 1, the first American satelliteAfter Russia launched the world’s first satellite, Sputnik, the Jet Propulsion Laboratory, which is now part of NASA, immediately began work on its own design. After three months of development, Explorer 1 launched and began circling Earth twelve and a half times per day until 1970, sending back crucial data, and setting the stage for future space exploration.1969: The moon landingThe first American in space, Astronaut Alan Shepard, spent 15 minutes in flight in 1961. Soon afterward, President John F. Kennedy announced that NASA would next send humans to the moon, and the Apollo program was established. In 1969, Neil Armstrong was the first person to set foot on the surface of the moon, and the world watched as he proclaimed, “That’s one small step for man, one giant leap for mankind.”1990: The Hubble Space TelescopeBefore the launch of the Hubble Space Telescope, our views into space were limited to what telescopes on the ground could show us. The first telescope in space, named after astronomer Edwin Hubble, revealed clear images of the universe beyond our galaxy for the first time.

1998: The International Space StationThe ISS wasn’t the first space station—Russia had launched two and NASA had sent up the failed Skylab in 1973—but it’s the most advanced. The first portions of the station were launched in 1998, with the first crew arriving in 2000. It’s been in use ever since, as the U.S. and several other countries send astronauts and equipment to study the cosmos on long-term programs.

1996: The Mars PathfinderLaunching in 1996 and landing on the Red Planet in July 1997, the Mars Pathfinder traveled 309 million miles and returned billions of pieces of information and thousands of photos back to Earth for one year. This unmanned mission cleared the way for many more Mars research projects, including today’s rover, Curiosity.

So, what’s next for NASA? You can look forward to these exciting new missions:2015: Expedition to PlutoThe New Horizons spacecraft launched in 2006 and is now halfway between Earth and Pluto, which is more than 9 billion miles away. The first mission to go such a distance, it’s planned to fly by Pluto and its moons in July 2015.2016: Exploring JupiterJuno, a spacecraft launched in 2011, has already traveled 785 million miles toward Jupiter, traveling 1.6 miles per second relative to Earth. Juno is scheduled to reach the giant planet to study its origins and atmosphere in 2016.2018: A visit to the sunThe Solar Probe Plus will launch in 2018 and will visit the sun’s outer atmosphere, which is, according to NASA, “arguably the last region of the solar system to be visited by a spacecraft.” The probe is planned to reach that historic destination by 2024.2025: First manned mission to an asteroidIn 2010, President Barack Obama announced plans to send humans to an asteroid by 2025. Currently, NASA’s Orion program is working toward making that promise a reality.2030: First manned mission to MarsEarth’s next biggest space achievement is undoubtedly sending humans to Mars. In 2010, Obama seemed sure of the milestone. “By the mid-2030s, I believe we can send humans to orbit Mars and return them safely to Earth. And a landing on Mars will follow. And I expect to be around to see it,” he said.